The present invention relates to a cruise control system for a vehicle.
There exists an adaptive cruise control system for a vehicle to mitigate the driving load on the driver of a car, for example, on a superhighway. To operate such an adaptive cruise control system of a car, the driver must manually push a button arranged on the handle of the car to start adaptive cruise control. In an ordinary fixed-speed control state in which the car follows a target or preceding car or in which the car is running straight, the driver needs to push only once the button to start adaptive cruise control. However, when the road is congested or when the road has many turns, the setting of adaptive cruise control is canceled each time the driver applies the brake. This leads to a problem of operation and safety that the driver must push the button to start adaptive cruise control each time the driver applies the brake. To overcome this problem, some methods are known. For example, JP-A-2000-142169 describes a method in which after the adaptive cruise control of a car is released, the adaptive cruise control is started again when the vehicle speed of the car reaches a predetermined speed to start adaptive cruise control by increasing the vehicle speed through operation of the accelerator pedal or accelerator.